Design of bio-based P-N synergistic aerogels: Integrating phosphorylated chitosan into sodium alginate for fire-safe thermal insulation

Fengfan Zhu; Huanhui Zhan; Chenfei Wang; Bo Fu; Jiancheng Zhou

doi:10.1016/j.jobab.2025.08.004

Volume 10 Issue 4

Nov. 2025

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Fengfan Zhu, Huanhui Zhan, Chenfei Wang, Bo Fu, Jiancheng Zhou. Design of bio-based P-N synergistic aerogels: Integrating phosphorylated chitosan into sodium alginate for fire-safe thermal insulation[J]. Journal of Bioresources and Bioproducts, 2025, 10(4): 545-559. doi: 10.1016/j.jobab.2025.08.004

Citation:

Fengfan Zhu, Huanhui Zhan, Chenfei Wang, Bo Fu, Jiancheng Zhou. Design of bio-based P-N synergistic aerogels: Integrating phosphorylated chitosan into sodium alginate for fire-safe thermal insulation[J]. Journal of Bioresources and Bioproducts, 2025, 10(4): 545-559. doi: 10.1016/j.jobab.2025.08.004

Citation:

Fengfan Zhu, Huanhui Zhan, Chenfei Wang, Bo Fu, Jiancheng Zhou. Design of bio-based P-N synergistic aerogels: Integrating phosphorylated chitosan into sodium alginate for fire-safe thermal insulation[J]. Journal of Bioresources and Bioproducts, 2025, 10(4): 545-559. doi: 10.1016/j.jobab.2025.08.004

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Design of bio-based P-N synergistic aerogels: Integrating phosphorylated chitosan into sodium alginate for fire-safe thermal insulation

doi: 10.1016/j.jobab.2025.08.004

a.
School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China
b.
Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China

More Information

Corresponding author: E-mail address: fubo@njfu.edu.cn (B. Fu); E-mail address: jczhou@seu.edu.cn (J. Zhou)
Received Date: 2025-04-24
Accepted Date: 2025-07-11
Rev Recd Date: 2025-06-26

Available Online: 2025-08-16

Publish Date: 2025-11-01

Abstract

Abstract

In response to the growing demand for sustainable thermal management solutions, this study developed an eco-friendly flame-retardant aerogel through a green manufacturing process that incorporates bio-derived phosphorylated chitosan (PCS) into a sodium alginate (SA) matrix. The strategic incorporation of PCS, synthesized from renewable chitin resources, significantly enhanced the interfacial compatibility and thermal stability of the composite material while introducing a phosphorus-nitrogen synergistic flame-retardant mechanism. Systematic characterization revealed that the sodium alginate mixed with 30% that mass of phosphorylated chitosan (SA-30 PCS) exhibits exceptional fire safety performance, achieving a limiting oxygen index (LOI) of 33.7% and a V-0 rating in the vertical burning test (Underwriters Laboratories Standard 94), which indicates the highest level of flame resistance. Additionally, this formulation shows a 45% reduction in total heat release compared to pristine SA aerogels. The composite maintains low thermal conductivity (0.035 0 W/(m·K)), fulfilling dual requirements for high-temperature insulation and fire protection. A sustainable hydrophobic modification strategy employing methyltrichlorosilane vapor deposition further endowed the aerogel with moisture resistance. As a wholly biomass-derived system (SA/PCS), the aerogel eliminates persistent toxic residues associated with halogenated flame retardants, while its phosphorus components are covalently bonded in polymeric chains, significantly reducing environmental mobility compared to inorganic phosphates. The inherent biopolymer composition enables potential end-of-life management via enzymatic digestion (e.g., chitinase/alginate lyase), positioning it as an eco-design alternative for sustainable insulation.
- Aerogel,
- Sodium alginate,
- Flame retardant,
- Thermal insulation

Declaration of competing interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
CRediT authorship contribution statement
Fengfan Zhu: Visualization, Formal analysis, Writing – original draft. Huanhui Zhan: Data curation, Formal analysis. Chenfei Wang: Visualization. Bo Fu: Conceptualization, Supervision, Funding acquisition, Writing – review & editing. Jiancheng Zhou: Supervision, Writing – review & editing.
Data availability
Data will be made available on request.
Supplementary materials
Supplementary material associated with this article can be found, in the online version, at doi:10.1016/j.jobab.2025.08.004.
Peer review under the responsibility of Editorial Office of Journal of Bioresources and Bioproducts.

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References(45)

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